This invention relates to methods and devices for charging, discharging and reconditioning batteries. More particularly, a novel method is disclosed for the rapid charging of batteries, the rapid discharging of batteries, and rapid reconditioning of batteries.
It is known in the art to charge a battery rapidly by applying a charging current with discharging intervals interspersed between the charging intervals. For instance, U.S. Pat. No. 3,609,503 to Burkett et al., describes the use of such depolarization of a battery by discharging it, which will allow a much larger charging current to be applied to the battery, thereby allowing a faster charge of the battery. In another U.S. Pat. No. 3,597,673, also issued to Burkett et al., such a rapid charge system is disclosed wherein the discharge path is applied during time between charge pulses. Since, in this implementation, the length and spacing of charge pulses is determined based on the frequency of the alternating power source and the charge of the battery, and since for rapid charging the discharge pulse must be relatively short, the disclosure points out that there may be a rest period before or after the discharge pulse. Furthermore, the duration of the discharge pulse may vary during the process of charging the battery. The rest period thus resulting is an incidental effect of the particular charging pulse generator method, and it was not recognized or claimed that an appropriate rest period may itself have beneficial results.
Furthermore, it is recognized that batteries have "memories" in that after a number of charges the ability of a battery to take on a satisfactory charge is inhibited. In such cases it is known to recondition a battery by repeatedly discharging the battery and recharging the battery. However, even with known rapid charging systems, such reconditioning is very slow due to the necessary discharge time with available discharge devices.